Long bones of mammals provide

Options

A. support only
B. support and produce RBCs only
C. support and produce WBCs only
D. support and produce RBCs and WBCs

Answer

### Step-by-Step Solution:

1. **Understanding the Structure of Long Bones**:
- Long bones consist of three main parts: the epiphysis (ends), metaphysis (the area between the epiphysis and diaphysis), and diaphysis (the shaft).

2. **Function of Long Bones**:
- The primary function of long bones is to provide structural support to the body. They help in maintaining posture and facilitate movement by acting as levers.

3. **Bone Marrow**:
- Inside the long bones, particularly in the diaphysis, there is a cavity filled with bone marrow. This marrow can be red or yellow, but the red bone marrow is crucial for blood cell production.

4. **Hematopoiesis**:
- The red bone marrow is responsible for the formation of blood cells, including red blood cells (RBCs), white blood cells (WBCs), and platelets. This process is known as hematopoiesis.

5. **Conclusion**:
- Therefore, the long bones of mammals provide structural support and are involved in the production of blood cells (RBCs and WBCs).

### Final Answer:
Long bones of mammals provide structural support and produce red blood cells (RBCs) and white blood cells (WBCs).

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